Math Moment – Automotive Technologies HS.A-REI.D.10 Understand that the graph of an equation in two variables is the set of all its solutions plotted in the coordinate plane, often forming a curve (which could be a line). Property of Pima County JTED 2014

Materials Needed Worksheet Worksheet Key Note-taker

Automotive Technologies Understand that the graph of an equation in two variables is the set of all its solutions plotted in the coordinate plane, often forming a curve (which could be a line).

Bellwork Give an example of something that is either on or off. Share with your partner. Be ready to share if called upon.

Vocabulary ordered pairs The pair of numbers that identifies a point on a coordinate plane. The first number is the x-coordinate and the second is the y- coordinate. Example (4, -3).

Vocabulary coordinate plane The plane determined by a horizontal number line, called the x-axis, and a vertical number line, called the y-axis, intersecting at a point called the origin. Each point in the coordinate plane can be specified by an ordered pair of numbers.

Vocabulary substitute Replace a variable with a numeric value and simplify.

Math Check Do the following ordered pairs make the equation 3x – y = 2 true? 1. (0, -2) 2. (1, -1) 3. (4, 10) 4. Find another ordered pair that makes the equation true.

Coordinate Plane

Plotting Points or Ordered Pairs

Do these points lie on the graph? 1. Substitute the ordered pair into the equation. 2. Simplify and determine if the statement is true or false. If the statement is true the point lies on the graph If the statement is false the point does not lies on the graph

Example 1 Which of the following points are on the line with equation ? a) (0, -3) b) (-4, -6) c) (4, -1)

Example 2 Do the following points lie on the line? a)(3, 2) b)(0, -3) c)(-1, -5)

Ohm’s Law and a Graphical Representation

Ohm’s Law Experiment AmpsVolts

Auto Example – Ohm’s Law

Exploration Use the graph on your note-taker to select the mostly likely solution to the equation represented by the graph. a) (12, 0.24) b) (0.15, 7.5) c) (0.24, 24)

You try! – Converting Temperatures To convert Celsius to Fahrenheit use the formula

Points on the Graph State the ordered pairs for the points A, B, C and D on the Temperature Conversion Graph.

Temperature Conversion A B C D

Example 3 Do the following points lie on the line? a)(1, 2) b)(-2, 4) c)(0, 1)

Example 4 Find 3 points that would lie on the graph of. Graph to verify.

Closure: Tweet a Friend PROPERTY OF AZ CTE CURRICULUM CONSORTIUM, 2013 Write a tweet to a friend or absent classmate explaining the learning using 140 characters or less